The government can do without 2,000 to 3,000 "surplus" air traffic controllers, and up to 3,000 others included among the nation's 17,200 controllers perform "activities which don't require controller training," White House spokesman David R. Gergen said yesterday.

As a result, federal officials say they have more than enough applicants to fill the essential 6,500 trainee positions left vacant by fired air traffic controllers, and the officials said they are speeding up their training program to put new controllers on the job as soon as possible.

Transportation Secretary Drew Lewis said 20,000 prospective applicants for the positions had contacted the government since the strike began Monday, and 9,000 applications were already on file.

In the meantime, more than about 75 percent of the nation's normally scheduled flights continued to move yesterday under an air traffic control system staffed by supervisors, military and non-striking regular controllers. The FAA said they were working 58-hour weeks, which would be reduced to 48 hours on Saturday, and even further next week as more military controllers are phased in. No one is allowed to work more than 10 hours per shift, the FAA said.

J. Lynn Helms, FAA administrator, said "the system continues to work well," although there will be "some inconvenience."

PATCO president Robert E. Poli said, however, "They're lying." He said he understood that controllers were working 12-to-14-hour shifts and were getting tired.

The Federal Aviation Administration yesterday asked the Pentagon for another 130 military air traffic controllers, raising to 500 the number of Air Force, Army and Navy personnel now helping out in control towers.

The vast majority of military controllers have not been directly involved in conducting air traffic because of lack of experience in the locations to which they have been assigned, the Air Force said.

Military controllers can continue relieving civilian staffers as long as needed, although there have been no definite plans made for long-term assignments to the towers, an Air Force spokesman said.

About 300 controllers who retired during the last couple of years have been determined to be qualified for work, and are being contacted about filling in during the strike, an FAA personnel spokesman said.

Some controllers are being moved from low-activity to high-activity airports requiring more skill, but this is a common procedure and has not been a problem during the strike, she said.

About 5,500 of the FAA applicants have already passed eligibility examinations, including psychological and physical tests, and tests to determine whether they can think "three-dimensionally" in order to handle altitude, latitude and longitude coordinates, she said.

This Tuesday the first class of 120 will begin 20 weeks of training at the Air Traffic Controller Academy in Oklahoma City, followed by two to four years of on-the-job training in air traffic control towers. Another class of 200 will begin Sept. 1. About 500 of the eligible trainees, most of them former military controllers, can go directly into on-the-job training because of prior experience.

"These people really want the jobs," the spokesman said. "We call and ask if they can be ready in five days to move thousands of miles away for weeks [of training] and most of them say they're ready to go."

By increasing the daily one-shift schedule to three shifts a day, the academy can easily triple its annual total of graduates, from 1,800 to almost 6,000, without endangering future air travel, a spokesman for the academy said.

The Office of Personnel Management this week waived the periods between promotions for controller trainees, which are required for civil servants, enabling trainess to advance to more difficult work levels as soon as they prove capable.

Some training phases may be shortened without jeopardizing the amount or quality of instruction said the FAA spokesman. A six-week program, for example, might be concentrated into four weeks, she said.

Usually controller academy graduates can reach journeyman status, the level required to work without supervision, in three years at low-activity airports and in five years at busy ones such as Los Angeles and O'Hare. The streamlined training procedure should enable controllers to reach those levels in about two to four years, the spokesman said.